private void btnComputeCrc_Click(object sender, EventArgs e)
{
Stopwatch sw = new Stopwatch();
sw.Start();
txtOutput.Text = Arinc702Crc.AppendCrcToMessage(txtInput.Text);
txtCrcValue.Text = txtOutput.Text.Substring(txtOutput.Text.Length - 4);
sw.Stop();
lblElapsedTime.Text = "Elapsed time: " + sw.Elapsed.ToString();
}
private void txtInput_TextChanged(object sender, EventArgs e)
{
StringBuilder sbHex = new StringBuilder();
StringBuilder sbBin = new StringBuilder();
StringBuilder sbBinNoSpaces = new StringBuilder();
List <byte> bytes = new List <byte>();
// transpose text for ARINC 702A
txtTransposed.Text = new string(txtInput.Text.Reverse().ToArray());
txtDenomBits.Text = txtDenominator.Text.Length.ToString();
if (txtDenominator.Text.Length > 0)
{
txtDenominatorExponents.Text = Arinc702Crc.GetBinaryExponentsString(txtDenominator.Text);
}
foreach (char c in txtTransposed.Text)
{
sbHex.Append(Convert.ToByte(c).ToString("X"));
sbHex.Append(" ");
sbBin.Append(Convert.ToString(c, 2).PadLeft(8, '0'));
sbBinNoSpaces.Append(Convert.ToString(c, 2).PadLeft(8, '0'));
//sbBin.Append(" ");
bytes.Add(Convert.ToByte(c));
}
txtHex.Text = sbHex.ToString();
txtBin.Text = sbBin.ToString();
txtTransposedBinary.Text = new string(sbBinNoSpaces.ToString().Reverse().ToArray());
txtExponents.Text = Arinc702Crc.GetBinaryExponentsString(txtTransposedBinary.Text);
TextBox tb = sender as TextBox;
if (tb != null && tb.Name == "txtInput")
{
// numerator = 1's compliment first 16 bits of transposed binary shifted left 16 bits
StringBuilder sbNumerator = new StringBuilder();
for (int i = 0; i < Math.Min(16, txtTransposedBinary.Text.Length); i++)
{
char c = txtTransposedBinary.Text[i];
if (c == '1')
{
sbNumerator.Append('0');
}
else
{
sbNumerator.Append('1');
}
}
for (int i = 16; i < txtTransposedBinary.Text.Length; i++)
{
sbNumerator.Append(txtTransposedBinary.Text[i]);
}
sbNumerator.Append("0000000000000000");
txtNumerator.Text = sbNumerator.ToString();
}
//// denominator = 10001000000100001 (16 12 5 1) -- this is actually a 17-bit CRC?
//txtDenominator.Text = "10001000000100001";
if (txtDenominator.Text.Length < 1)
{
txtDenominator.Text = "10001000000100001";
}
if (txtDenominator.Text.Length < 2 || txtNumerator.Text.Length < 2)
{
return; // don't keep going with a 1 bit denominator
}
// 1. left shift denominator to same digits as numerator
// 2. xor numerator and denominator
// 3. next line is next numerator
// 4. when can't do it anymore, you have the remainder
txtLongDiv.Text = "";
string thisNumerator = txtNumerator.Text;
string thisDenominator;
string thisRemainder = thisNumerator;
if (thisNumerator[0] == '0')
{
thisDenominator = "0".PadRight(txtNumerator.Text.Length, '0');
}
else
{
thisDenominator = txtDenominator.Text.PadRight(txtNumerator.Text.Length, '0');
}
while (thisNumerator.Length >= txtDenominator.Text.Length)
{
thisRemainder = Arinc702Crc.BinaryStringXOR(thisNumerator, thisDenominator);
txtLongDiv.AppendText("N: " + thisNumerator + "\n");
txtLongDiv.AppendText("D: " + thisDenominator + "\n");
txtLongDiv.AppendText("R: " + thisRemainder + "\r\n\r\n");
thisNumerator = thisRemainder.Substring(1); // throw away leading zero
if (thisNumerator.Length > 0 && thisNumerator[0] == '0')
{
thisDenominator = "0".PadRight(Math.Max(thisNumerator.Length, txtDenominator.Text.Length), '0');
}
else
{
thisDenominator = txtDenominator.Text.PadRight(thisNumerator.Length, '0');
}
}
txtRemainder.Text = thisNumerator; // the last remainder minus the leading zero is the final value
StringBuilder sbCrc1 = new StringBuilder();
txtCrc1.Text = Arinc702Crc.BinaryStringInvert(txtRemainder.Text);
txtTransposedCrc.Text = Arinc702Crc.BinaryStringTranspose(txtCrc1.Text);
txtHexCrc.Text = Arinc702Crc.BinaryStringToHexCharacterVals(txtTransposedCrc.Text);
txtMsgBackwards.Text = txtHexCrc.Text + txtTransposed.Text;
txtFinalMsg.Text = new string(txtMsgBackwards.Text.Reverse().ToArray());
txtClassTest.Text = Arinc702Crc.AppendCrcToMessage(txtInput.Text);
}
